A comparison of hay, wilted silage and formaldehyde prepared silage fed to lactating dairy cows.

Abstract

Proc. Aust. Soc. Anim. Prod. (1978) 12: 170 A COMPARISON OF HAY, WILTED SILAGE AND FORMALDEHYDE-PREPARED SILAGE FED TO LACTATING DAIRY COWS S.C. VALENTINE* and R.B. WICKES* Milk production is generally higher from dairy cows offered hay than those offered silage made from herbage cut at the same time. Wilting or treating herbage with formaldehyde before ensiling may increase the milk production by dairy cows fed silage. This paper describes an experiment to compare the intake and milk production by dairy cows fed hay or three silages made from either untreated herbage (U-silage), herbage wilted to 31 per cent dry matter (W-silage) or herbage treated with formaldehyde at 0.8 per cent .of the dry matter (F-silage). rigidm cv. Wimmera) - subterranean clover (~TrifoZiwn.subterranewn) - A phalaris (Phalaris $uberosa)-annual rye grass (Lo&m annual medic (Medicago truncatda, M. rugosa) pasture'was conserved by either harvesting with a double-chop forage harvester or mowing with a rotary slasher and thenbeing either picked up with the forage harvester after 24 hpurs wilting or baled for hay after three days drying. The herbages were compacted into bunkers and covered with ' The hay was stored under cover. ' plastic. Thirty-two grade Friesian cows were individually fed the same silage for a one week covariance period and'then randomly assigned to The test diets were fed ad .%bitwn for six weeks and the four diets. each cow received 4.5 kg,of a barley-meatm&+concentrate daily. Daily feed intakes, milk yields and yields and' percentages of milk fat, protein and solids-not-fat (SNF) were recorded from weeks three to six inclusive for each cow. Daily liveweight gains of cows from weeks three to six and the covariance corrected intake and milk production data are shown in Table 1. The results indicate that the nutritive value of silage for milk protein production is higher if the herbage is wilted rather than Although cows fed wilted sprayed with formaldehyde before ensiling. silage may produce similar amounts of milk fat and protein to those fed hay they can consume significantly more dry matter which can be utilised for liveweight gain. *Northfield Research Centre, Department of Agriculture and Fisheries, Box 1671,G.P.o., Adelaide, South Australia. 5001. 170,